|VAN IMMERSEEL, FILIP|
Submitted to: FEMS Microbiology Letters
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/11/2008
Publication Date: 1/21/2009
Citation: Gantois, I., Ducatelle, R., Pasmans, F., Haesebrouck, F., Gast, R.K., Humphrey, T., Van Immerseel, F. 2009. Mechanisms of egg contamination by Salmonella Enteritidis. FEMS Microbiology Letters. 33:718-738.
Interpretive Summary: Salmonella Enteritidis has been a major cause of food-borne illness around the world during the last 20 years. Eggs, which can be contaminated either on the outer shell surface or in the contents, have been the most important vehicle of infection. Internal contamination can result from either penetration of bacteria through the shell or by direct deposition into the contents before the egg is laid as a result of infection of reproductive organs. Once inside the egg, bacteria must survive exposure tp antimicrobial factors in the egg white before migration to the yolk can occur. Serotype Enteritidis appears to have intrinsic factors that result in a unique epidemiological association with eggs, although these have not yet been defined. There is evidence that Salmonella Enteritidis can survive the attacks by antimicrobial molecules during the formation of the egg in the hen’s oviduct and inside the egg, perhaps due to a unique combination of genes encoding for improved cell wall protection and for repairing cellular and molecular damage.
Technical Abstract: Salmonella Enteritidis is the major cause of the food-borne salmonellosis pandemic in humans of the last 20 years, during which contaminated eggs were the most important vehicle of the infection. Eggs can be contaminated on the outer shell surface and internally. Internal contamination can be the result of penetration through the eggshell or by direct contamination of egg contents before oviposition originating from infection of reproductive organs. Once inside the egg, the bacteria need to cope with antimicrobial factors in the egg white, before migration to the yolk can occur. It would seem that serotype Enteritidis has intrinsic characteristics resulting in an epidemiological association with hen eggs, which are yet undefined. There are indications that Salmonella Enteritidis survives the attacks by antimicrobial molecules during the formation of the egg in the hen’s oviduct and inside the egg. This appears to require a unique combination of genes encoding for improved cell wall protection and repairing cellular and molecular damage, amongst some others.